Evercontact - Your contacts always up to date and automatically with Evercontact.

Thunderbird - Thunderbird is a free email application that's easy to set up and customize - and it's loaded with great features!

Pobuca Connect - Connect with your contacts.

Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.

SutiCLM - Online contract management software for faster contract cycles and total compliance

eM Client - eM Client is a fully-featured email client for Windows and macOS with a clean and easy-to-use interface. eM Client also offers features for calendars, tasks, contacts, notes, and chat.